tractorsfandomcom-20200215-history
Three-wheeled car
A three wheeled car, also known as a tricar or tri-car, is a powered vehicle, legally classed as either an automobile or motorcycle, that has one wheel in the front and two at the rear, or two in the front and one in the rear. Due to its handling superiority, an increasingly popular form is the front-steering "tadpole" or "reverse trike" sometimes with front drive but usually with rear drive. A variant on the 'one at the front' layout was the Scott Sociable, which resembled a four-wheeler with a front wheel missing History Early car pioneer Karl Benz developed a number of three-wheeled models. One of these, the Benz Patent Motorwagen, is widely regarded as the first purpose-built automobile. It was built in 1885. In 1896, John Henry Knight showed a tri-car at The Great Exhibition. In 1897, Edward Butler (inventor) made the Butler Petrol Cycle, another three-wheeled car. A Conti 6 hp Tri-car competed in (but did not complete) a 1907 Peking-to-Paris race sponsored by a French newspaper, Le Matin. Three wheeler configuration Two front A configuration of two wheels in the front and one wheel at the back presents two advantages : it has improved aerodynamics, and that it readily enables small lightweight motorcycle powerplant and rear wheel to be used. This approach was used by Messerschmitt kr200 and by the BMW Isetta. Alternatively, a more conventional front-engine, front wheel drive layout as is common in four-wheeled cars can be used, with subsequent advantages for transversal stability (further front location of CG) and traction (two driven wheels instead of one). For the lowest wind resistance (which increases fuel efficiency), a teardrop shape is desirable . A tear drop is wide and round at the front, tapering at the back. The three wheel configuration allows the two front wheels to create the wide round surface of the vehicle. The single rear wheel allows the vehicle to taper at the back. This approach is used by the Aptera 2 Series. It is also used by Myers Motors for both its single passenger NmG and upcoming 2-passenger Duo. Two rear Having one wheel in front and two in the rear for power reduces the cost of the steering mechanism, but greatly decreases lateral stability when cornering while braking. Lateral stability The disadvantage of a three wheel configuration is lateral instability - the car will tip over in a turn before it will slide, unless the centre of mass is much closer to the ground or the wheelbase is much wider than a similar four wheel vehicle. Electric three-wheelers often lower the center of gravity by placing the heavy battery pack at the base of the vehicle. Tilting option To improve stability some three wheelers are designed as tilting three wheelers so that they lean while cornering like a motorcyclist would do. The tilt may be controlled manually or by computer. Examples For a more complete list, see Category:Three-wheeled motor vehicles. Two Front Wheels models : Two Rear Wheels models : Registration In the U.S. the National Highway Traffic Safety Administration defines and regulates three-wheeled vehicles as motorcycles. Licensing requirements vary on a state-by-state basis. In other jurisdictions, such as British Columbia, Canada, and Connecticut, a three-wheeled vehicle with an enclosed passenger compartment or partially enclosed seat is considered an automobile. See also *Three wheeler *Motorized tricycles *Electric trikes *Tuk-tuk or Auto rickshaw - Three wheeled vehicles popular in many parts of Asia *Steam tricycle *Cushman - manufactured in USA, many built for utility/maintenance *Tri-Magnum - a DIY three-wheeler *Myers Motors NmG - all-electric plug-in, manufactured in USA *Volkswagen_1-litre_car References External links * History of the Three Wheeler * "Three Wheel Cars; Primary Factors that Determine Handling & Rollover Characteristics" * Link index for three wheeled cars as well as other types Three-wheeled motor vehicles